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Subject: Re: Bug in scheduler when using rt_mutex
From: Mike Galbraith <efault@gmx.de>
To: Ingo Molnar <mingo@elte.hu>
Cc: Yong Zhang <yong.zhang0@gmail.com>, Peter Zijlstra <peterz@infradead.org>,
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        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
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Date: Wed, 19 Jan 2011 08:41:05 +0100
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On Wed, 2011-01-19 at 08:19 +0100, Ingo Molnar wrote:
> * Mike Galbraith <efault@gmx.de> wrote:
> 
> > On Wed, 2011-01-19 at 14:09 +0800, Yong Zhang wrote:
> > > On Wed, Jan 19, 2011 at 1:40 PM, Mike Galbraith <efault@gmx.de> wrote:
> > > > On Wed, 2011-01-19 at 12:35 +0800, Yong Zhang wrote:
> > > >
> > > >> cfs_rq->curr != se is always true.
> > > >
> > > > If that were always true, we'd illegally enqueue a running task.
> > > 
> > > I'm sorry that I'm not express myself correctly.
> > 
> > Human communication methods are all buggy as hell :)
> 
> Not to mention that they are slow, inefficient and ambiguous.
> 
> But wht did you expect? The original authors of the code are long gone and 
> maintenance is done by newcomers who are patching the code bit by bit. What
> you get from such a development model is pretty predictable: ~1 billion years
> old spaghetti DNA that no-one truly understands.

Gotta give the original authors credit though, their self modifying code
comes equipped with a fully automated hardware break-point debugger.

	-Mike